A new CEO appointment would come at a time of major upheaval at the 136-year-old institution - a legacy of Britain's former manufacturing clout - that remains the world's biggest marketplace for aluminium, copper, lead, zinc, tin and nickel.

The LME was sold to Hong Kong Exchanges and Clearing last year for $2.2 billion in a move reflecting China's new industrial prominence.

For now, men in business suits conduct often raucous "open-outcry" trading around a circular "ring" at the LME's Leadenhall St. headquarters in London's City business district, observing traditions that date to the exchange's coffee house origins.

There was a woman ring trader but she left.

Much trade on the LME is done electronically or by telephone, rather than in the ring itself, and women are active as traders, clients and exchange staff.

Fix-it skills much needed

Fix-it skills are much in need at the LME just now.

Fury is growing among its industrial clients, who blame the exchange for letting agonisingly long queues build up for material they have bought via the LME and want to withdraw from warehouses in the global network it oversees.

They say LME rules allow firms running warehouses to make money by building up big stocks and charging for storage while they deliver metal out at a limited rate.

"With Abbott, the big proponent of no change, leaving, the LME is in a better position to make changes to placate customers," one metals industry source said.

The issue of warehouse backlogs almost derailed the takeover last year.

The latest complaints this week came from The Beer Institute, which represents global brewers and their suppliers struggling to get aluminium for cans at a reasonable price.

It wants an end to the "restrictive and outdated warehousing rules and practices that are interfering with normal supply and demand dynamics" and changes to bring the LME's warehousing practices in line with other global commodity exchanges.

Meanwhile the CME, where Ms Hunnable works, is looking at expanding its warehouse network as its COMEX copper contract eats into the LME's dominance in global copper futures.

"It could be a he, it could be a she"

HKEx CEO Charles Li, asked in Hong Kong about the search for a new LME head, replied, "It could be a he, it could be a she."

"Everything is on the table," he told Reuters on the sidelines of LME Week Asia, an industry gathering now under way in Hong Kong.

"We have some very, very high calibre individuals. We have a great franchise and we have great world class leaders. We are very lucky and we are in discussions."

With European regulators ready to impose new rules on financial markets, the LME's chief operating officer Diarmuid O'Hegarty is well placed. A solicitor, he became LME executive director of regulation and compliance in 2004, deputy chief executive in 2008 and COO earlier this year.

"He is a strong contender," one metals industry source said.

Other possibilities are Martin Pratt, chief operating officer at metals trader Triland, and Gavin Prentice, former managing director and global head of sales for Marex Spectron.

But most sources say it's likely that the next CEO will come from another exchange.

Romnesh Lamba, HKEx co-head of global markets division, said the new CEO was unlikely to come from the Hong Kong exchange and he or she would have to meet British and European regulatory requirements. He ruled himself out as a contender.